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Topic: Fermenting Belgians (Read 1314 times)

I'm looking to start do a few Belgians. Going through many recipes, many of them state that you should start fermenting at colder temps then ramp up the temps at some point during fermentation. Specifically, I'm looking at a saison recipe that says to start at 67° and ramp up to 80° over the course of fermentation.

How would I handle upping the temp? A degree or two a day?

Other recipes say to ramp up the temps during the last third of fermentation. How do you know how many days of fermentation you're looking at. Is a best guess? Or does knowing come from experience?

Use gravity check to determine whether it is finished fermenting, rather than depending on a number of days. Belgians will vary with their OG, and expect the bigger ones to primary for several weeks or more.

Use the temperature range provided by the yeast manufacturer as a guideline. In general I pitch on the cool side of this range, and let it free-rise to the higher end as growth and fermentation progresses. Once it stops rising, I try to hold it at that temperature until fermentation stops. With Belgians, be careful of temperatures in the high 70s and 80s as they can cause a significant fusel character. The exception to this is the saison yeast, which can (and in most cases need to) go to the 80s and even sometimes into the 90s. WLP565 is a notoriously finicky saison strain--don't be surprised if it takes a break and then starts again, although you might have to gently rouse it and raise temp to get it to finish dry like it is supposed to. The results are worth it if you have the patience.

Another good temperature resource if you are brewing the Trappist styles is "Brew Like a Monk" by Stan Hieronymus. He has guidelines on the characters created by the various Trappist strains.

What Joey said - except that for Saisons I would recommend the book "Farmhouse Ales" by Phil Markowski Definitely don't get carried away on the heat. I have even fermented WLP565 to full attenuation in the high 60s before. That said, it can be hard to predict how this yeast will behave from batch to batch, especially on higher gravity beers.

Eventhough DuPont Saison ferments in the 80-90 F range, I would recommend 65-80 tops with single cell strains and I believe you will be happy with the results.Start in the upper 60's and let it slowly ramp to the mid to upper 70's.

It isn't so much that you raise temperatures, it's that you don't constrain the temperatures. The temperature will rise from the fermentation -- let it go. If you artificially keep the temperatures down by putting it in a water bath, for instance, the yeast generally won't be happy.

From your POV, you pretty much keep the fermenter the same (assuming ambient room temperature, not a chilled environment) and the yeast will be fine.

Moving it to a warmer location at the end does tend to help them finish, depending on the strain.

The Saison yeast is different, but the above advice is pretty consistent for most other Belgian yeasts and is pretty much what I heard from brewers when over there. They'll start at different temperatures, but once they start, they let the yeast run.

It isn't so much that you raise temperatures, it's that you don't constrain the temperatures. The temperature will rise from the fermentation -- let it go. If you artificially keep the temperatures down by putting it in a water bath, for instance, the yeast generally won't be happy.

I'm pretty sure that some Belgian brewers do restrain temps. For instance, Westmalle and Westvleteren use the same yeast, but Westmalle caps the fermentation temp at 68 while Westvleteren "lets it rise" to the low 80s.

Also, since we have much smaller fermentation vessels we can not reach the same exothermic potential as a, say, 100bbl batch. So if you want to let it rise into the 80s it may be necessary to add some external heat. I use a thermowell, temp controller and heat wrap.

I recently fermented a 10 gallon batch using 3724 and it fermented out fine in 6 weeks. I used a starter and pitched onto 64 degree wort which was the only real constraint I placed on it. I kept it there (partially submersed the vessel in a creek) for two days, then moved it onto the bank in the shade for four days and then to my shed and let it run its course unhampered. My fermometer only goes to either 78 or 80 degrees so I don't know if it went above that. Most of the time it was between 74 and 76 degrees on the strip and only peaked above that a couple of times on days that were very hot.